Extend ResourceLoader API for retrieval of (all / only filtered) cached paths in (C++, C#, GDScript)

[TruelyMostWanted]

Hey, this is my first PR / contribution to the engine 👋

Description:

This PR extends the ResourceLoader by 4 public methods for retrieval of either all or only filtered cached paths in C++, GDScript and C#.

Note A Resource is considered cached when it has a Reference Count > 0. This means it got assigned to exported fields in inspector or via set(...) / set_deferred(...) in code.

Usages:

extends Node
class_name GdScriptTestNode

@export var resources : Array[Resource]

func _ready() -> void:
	var allPathsArray = ResourceLoader.get_cached_paths()
	print(JSON.stringify(allPathsArray, "\t"))

	var allPathsDict = ResourceLoader.get_cached_paths_typed();
	print(JSON.stringify(allPathsDict, "\t"));

	var allImgPaths = ResourceLoader.get_cached_paths_by_filter(
		ResourceLoader.FilterTarget.FILTER_TARGET_TYPE_HINT,
		ResourceLoader.FilterComparator.FILTER_COMP_EQUALS,
		"Image"
	);
	print(JSON.stringify(allImgPaths, "\t"))
	
	var resPaths = ResourceLoader.get_cached_paths_typed_by_filter(
		ResourceLoader.FilterTarget.FILTER_TARGET_PATH,
		ResourceLoader.FILTER_COMP_BEGINS_WITH,
		"res://new"
	);
	print(JSON.stringify(resPaths, "\t"))

using Godot;
using Godot.Collections;

[GlobalClass]
public partial class TestNode : Node
{
    [Export] public Array<Resource> Resources;

    public override void _Ready()
    {
        var allPathsArray = ResourceLoader.GetCachedPaths();
        GD.Print(Json.Stringify(allPathsArray, "\t"));
        
        var allPathsDict  = ResourceLoader.GetCachedPathsTyped();
        GD.Print(Json.Stringify(allPathsDict, "\t"));
        
        var allImgPaths  = ResourceLoader.GetCachedPathsByFilter(
            ResourceLoader.FilterTarget.TypeHint, 
            ResourceLoader.FilterComparator.Equals, 
            "Image"
        );
        GD.Print(Json.Stringify(allImgPaths, "\t"));
        
        var allResPaths  = ResourceLoader.GetCachedPathsTypedByFilter(
            ResourceLoader.FilterTarget.Path, 
            ResourceLoader.FilterComparator.BeginsWith, 
            "res://new"
        );
        GD.Print(Json.Stringify(allResPaths, "\t"));
    }
}

Result:

With the above GDScript/C# and my list of resources (on the left) assigned to export variables i get the following result:

Documentation with Examples In-Engine

I hope this helps a lot of your projects out! ✨
Feel free to give me any feedback on the idea, the PR, the description/text of the PR and such

• Bugsquad edit, closes: Add retrieval methods to ResourceLoader for querying cached resource paths (C++, C#, GDScript) godot-proposals#13523

[AThousandShips]

This looks promising and quite minimal in scope, just doing a form pass

[AThousandShips]

This looks promising and quite minimal in scope, just doing a form pass

[AThousandShips]

Please apply all the suggestions locally and push once to reduce noise, if you weren't a first time contributor this would have triggered several runs of CI unnecessarily

[TruelyMostWanted]

Please apply all the suggestions locally and push once to reduce noise, if you weren't a first time contributor this would have triggered several runs of CI unnecessarily

Oh thats really good to know!
For me this was the first time having an actual code review on GitHub, so once again something learned, thanks!
The next thing i have to learn is rebasing commits into one. Reducing the commit history as seen above

But aside from that, my commits are done @AThousandShips

[AThousandShips]

You've skipped several suggestions, and didn't quite follow the suggestions given, but will do a second pass of review after you've added the missing ones (the very first one about spacing)

[TruelyMostWanted]

Code has been updated and all comments resolved.
Even though it shows me a (2) towards "Review changes" i dont see any further ones with status "Pending" or where i have the button to "Add changes to batch"

[TruelyMostWanted]

You've skipped several suggestions, and didn't quite follow the suggestions given, but will do a second pass of review after you've added the missing ones (the very first one about spacing)

But i did revert the file(s), adding in only what i changed, adding whitespaces between my methods and applied clang-format
There is definitly something missing on my side.

[AThousandShips]

Check the "changed files" and you'll see the changes that are left there, in resource.h and core_bind.cpp

I'll do another review tomorrow

[TruelyMostWanted]

Check the "changed files" and you'll see the changes that are left there, in resource.h and core_bind.cpp

I'll do another review tomorrow

Alrighty, thanks for your help though! Appreciate it very much!

[TruelyMostWanted]

Yey, my first rebase of commits worked, nice!
Now i get the hang of it

While working:

• Check on the styling/design guidelines in the docs (e.g., usage of auto, formatting the docs)

Pre-Commit:

• Run clang-format to enforce style guide

Rules for Commits and Pushs:

• Commit as much as i need locally but DO NOT PUSH IMMEDIATLY
• Then git rebase all commits into a single Squash Commit with a reworded commit message
• Push the Squashed commit (commit only when everything is really done) --> Note: After no longer being a First-Time Contributer, this will automatically trigger the CI/Actions and its Checks

Side note:
Find the right moment to open the Pull-Request. Knowledge extends, Discussions and Feedback happen and maybe even Code Reviews cause you to rewrite code and documentation. Thereby always follow the 3 steps above

Now i'm really done committing on this feature

[TruelyMostWanted]

Hey, i've made a test and noticed a difference in behaviours which we should talk about:

Behaviour (1) and (1.1):

❓(Questionable) Every Resource that gets loaded via any of the specific classes (e.g., AudioStreamWAV, AudioStreamMP3, Image, etc.. ) and their load_from_file(path) method is not automatically considered cached upon assignment to any variable in code.
It needs a manual assignment of the resource_path in GDScript or C#.

Behaviour (2):

✅ (Works as intended) Resource loaded via the ResourceLoader.load(path, typeHint, cacheMode) are automatically considered cached when assigned to any variable in code. This happens due to their internal call and assignment of the resource_path via

load_task.resource->set_path(load_task.local_path); //resource_loader.cpp, Line 446

which lead to resource.cpp handling the existence in ResourceCache::resources

void Resource::set_path(const String &p_path, bool p_take_over) { //resource.cpp, Line 70

Question

How should we handle this?
Shouldn't the different load_from_file(const String &p_path)methods automatically set the resource_path to the path given in their p_path parameter? It would only need 1 line of code in each of them to fix this:

resource->set_path(p_path);